Department of Vegetable Crops Punjab Agricultural University, Ludhiana
Online published on 28 June, 2012.
Eight genetically divergent parental lines were crossed in a diallel pattern to investigate general and specific combining ability alongwith extent of heterosis for quality traits and reaction to downy mildew. The combining ability analysis revealed that both gca and sca variance was significant for all the characters. Non-additive gene action played a major role in controlling the characters like TSS, total carotenoids, vitamin C, total mineral matter, reaction to downy mildew, bitterness and shelf life of fruit. On the basis of gca effects, parent Poinsette for TSS and vitamin C, Summer Khira for shelf life of fruit, SAKU-6 for reaction to downy mildew and bitterness, EC-27075 for total carotenoids and Sel-97-7 for total mineral matter were the best general combiners. Specific combining ability analysis revealed that hybrids Long Green x EC-27075 for TSS; Long Green x Bhari Mansa for total carotenoids and bitterness; Bhari Mansa x EC-27075 for vitamin C; Sel-97-7 x Summer Khira for total mineral matter; Poinsette x Summer Khira for reaction to downy mildew and Summer Khira x KH-1 for shelf life of fruits, showed highest sca effects. Cross combination long green x bhari mansa manifested maximum heterosis over better parent for vitamin C and over standard check for shelf life of fruit. Hybrid Long Green x Bhari Mansa registered best overall performance for studied quality traits.
Combining ability, Cucumber, Diallel analysis, Downy Mildew, Heterosis, Quality
